I'll agree to a point. There is no way you can argue we were in a good cap situation in 2017. Clays deal at 9 mil, cordy glenn getting paid a ton to play half a year. Not good deals. Dareus may have had a top 5 bad contract in the NFL in 2017. None of those guys are all-pros, or even pro-bowlers - and they're like 3 of the top 6-7 paid players on your team.
He inherited a mediocre team of overpaid players. He made moves to get the team in a healthier cap situation so that they can comfortably decide who to extend, and have some foresight into how much and when to give out those contracts. Could we have signed gilmore in 2017? Probably - but then its unlikely that you find hyde and poyer. We also had the Tyrod contract looming large at the time. Another little doug whaley gift.

They all made QB moves - Bledsoe, Losman, Edwards, Fitz extension, EJ, Tyrod extension....
It always comes back to that anyway. Beane made the moves necessary to get Allen. If Allen works out - most of the rest won't matter as much. If not - he's going to have to build something special to get another chance to draft a QB.

What you want is fewer 1st downs. You can get there with a lower 3rd down %, but generally fewer first downs will result in fewer plays. Fewer plays will result in fewer yards. Fewer yards will result in fewer points.
This puts your offense on the field more trying to do the opposite. More plays, more yards, more points.
Red zone execution is another important piece, but thats what i consider the basis of good defense.

If we don't see him coming back for next year - his contract is easy to get out of next year. This is good news for guys like dimarco, croom, sweeney, and fisher. With Smith and knox likely already penciled in on the roster pending trades/cuts.
If knox/smith show up and are solid - he can be cut next year very easily. If not, we have him as an option next year to compete.
Do we know the timeline on the injury?
Well, we put ourselves there by eating a ton of dead cap the last 2 years. But most GM's who came in were unwilling to do that so they'd just compound the issue by pushing deals out. A rebuild starts with a tear down usually.

The best 2 players available are Suh and McCoy - neither hit comp pick formulas - and neither has a ring. Seems like they'll either go where they can get overpaid on a 1yr deal, or go to a contender with space.
Cleveland, Indy, Seattle look like good destinations. More cap than buffalo in 2019 - anticipated playoff teams - spot to start without a competition.
I expect both to wait a bit to sign though - why go to OTAs and camp if you dont have to?
As i wrote this it said the bucs are trying to sign Suh. Must be cheaper than McCoy?

afaik there is no new money hitting the 2019 cap - but sportrac hasn't been updated yet. Would be adds for 2020 and 2021
He's also like - a big buffalo guy. This isn't a street free agent overpay. Its a guy 2 years in with McD who wants to be here.

This is all not factoring in releasing some roster bubble guys, keeping some UDFAs, etc.
This is how much we save by cutting any of these guys. You have to bring up any of the guys who get paid like 500k or less when factoring it in as we have 27 mil in cap space per the top 51. https://www.spotrac.com/nfl/buffalo-bills/cap/
Dimarco 1.1
Waddle 1.6
Kevin johnson 2.3
Bodine 2.3
Stanford 1.4
and the big one would be shady - that'd save 6.3 if we felt he wasn't going to help the team this year (i don't think there's a reason to cut him unless the new guys outplay him)